The present invention relates to a stern tube seal of the mechanical type which is used as a stern tube sealing device of ship.
In the past, mounting accuracy of a stern tube of the kind as described greatly varies depending on the condition of goods loaded within a ship or on the movement of ship so as not to be able to sufficiently follow displacement of a rotating shaft (stern tube) with respect to a stern frame (that is, on the hull side), giving rise to a leakage of seal fluid. Accordingly, it has been desired eagerly to enhance the performance of seal.